John Kilroy, Sr., founder and company chairman of Kilroy Realty Corp., has retired and his son John Kilroy, Jr. has replaced him as head of the company.

“My father helped create what, today, we take for granted—a professional real estate industry committed to meeting the needs of individual tenants and minimizing the capital investment and management responsibilities associated with owning commercial property,” the younger Kilroy said in a prepared statement.

It was in 1947 when Kilroy, Sr. founded KRC’s predecessor businesses and he has led as the publicly traded real estate investment trust’s chairman since its initial public offering in 1997.

Under Kilroy, Sr.’s leadership, the company became a multi-million-square-foot real estate enterprise, relying on the tremendous growth opportunities represented by the West Coast’s emerging aerospace and defense industries following the end of World War II.

John Kilroy Sr.

Kilroy, Jr. has run the day-to-day aspects of the business since 1981 and has been its president, CEO and a director since its incorporation in September 1996. He was the obvious choice when the board met to announce Kilroy, Sr.’s replacement this year, having led its private predecessor, Kilroy Industries in a similar capacity.

He previously served on the board of governors of the National Association of Real Estate Investment Trusts and the board of New Majority California, and is a trustee of the El Segundo Employers Association and past trustee of Viewpoint School, the Jefferson Center For Character Education, and the National Fitness Foundation.

For more than 65 years, KRC has owned, developed, acquired and managed real estate assets primarily in the coastal regions of Los Angeles, Orange County, San Diego, the San Francisco Bay Area and greater Seattle. It’s assets totaled more than 13.2 million rentable square feet of commercial office space as of end of 2012.